1. Field of the Invention
The present invention relates generally to a key for use in a piano and so on, and more particularly, to a key which has a weight attached thereto to provide a desired touch load.
2. Description of the Prior Art
Generally, in a keyboard-based musical instrument, particularly, an acoustic piano such as a grand piano, weights are attached to a key to provide a desired touch load (static load) for the key. Conventionally, the weights are typically made of lead. As illustrated in FIG. 1, a plurality (two in this example) of weights 53 each made of lead of a predetermined size molded into a cylindrical shape are embedded into a plurality of embedding holes 54 formed through a key body 52 made of wood of a key 51 at predetermined positions in front of a balance pin (not shown), and caulked for attachment to the key body 52. The lead is employed as the weights 53 in this manner because the lead has a high specific gravity (approximately 11.3) among other metals, is inexpensive, and exhibits high flexibility and ductility which facilitate works as mentioned above.
Generally, the touch load may be adjusted after the weights 53 have been attached as described above for purposes of eliminating variations in touch load among keys and of matching the touch load for a player""s preference. For adjusting the touch load, a side face of a weight 53 is cut away for reducing the touch load since the weight 53 is attached by caulking and therefore removed with difficulties. On the other hand, for increasing the touch load, at least one of previously provided separate adjusting weight 55, made of lead, is additionally attached to the key body 52, as indicated by broken lines in FIG. 1, for the same reason. In this event, a position for attaching the adjusting weight 55 is first determined such that the moment imparted by the adjusting weight 55 about the balance pin is appropriately produced in accordance with the touch load to be added. Then, an embedding hole 56 is additionally formed at the determined attaching position on the key body 52, followed by caulking the adjusting weight 55 for attachment to key body 52. These works are performed for each key 51.
In the conventional key 51 described above, lead is used as the material for the weights 53 for the reasons mentioned above. However, since lead is an injurious material, it is desirable that lead is used for the weights of the keys as least frequently as possible, so that an alternative material is needed for substitution for lead. Also, since the conventional key 51 involves caulking for attaching the weights 53 to each key body 52, this work itself is laborious. Also, since the weight 53 is attached by caulking, the key body 52 is susceptible to cracking due to an impact produced by caulking if the embedding holes 54 are formed at small intervals b, resulting in a limitation in the number of weights 53 attached to the key body 52. Further, due to difficulties in removal of the weights 53 attached by caulking, the adjustment of the touch lead involves the works which include cutting away the side face of each weight 53, forming the embedding hole 56 into the key body 52 while determining the position at which the adjusting weight 55 is attached, and attaching the adjusting weight 55 for each key 51, as described above. As a result, the adjusting works require significant efforts, resulting in an increase in the manufacturing cost.
The present invention has been made to solve the aforementioned problems, and it is an object of the invention to provide a key which is capable of facilitating the attachment of weights, and adjustments of a touch load, while using an alternative material for substitution for lead as a material for the weight.
To achieve the above object, the present invention provides a key for a musical instrument which is characterized by comprising a swingable key body formed with an embedding hole, and a weight made of a material other than lead and having a threaded outer peripheral surface, wherein the weight is removably fitted in the embedding hole of the key body to a give a load to the key body.
In this key, the weight is made of a material other than lead, and is removably fitted in the embedding hole formed through the key body to give a load to the key body. In this way, since the weight is fitted into the embedding hole by screwing in the present invention, the key body is free from cracking, which would be caused by an impact during caulking as is the case with the conventional weight, even if the embedding holes are formed at small intervals, so that an increased number of weights of can be attached to the key body. It is therefore possible to ensure a load equivalent to or approximate to weights made of lead, even with weights made of a material which is lighter than lead, for example, an approximately metal having a high specific gravity, as a material for the weight. As a result, such a material other than lead can be used as an alternative material for substitution for conventionally used lead. In addition, since the weight is screwed into the embedding hole using a tool, the attachment of the weight to the key body is facilitated, as compared with caulking conventionally used for attaching a weight. Further, since the weight is removable fitted in the embedding hole, the weight can be readily exchanged with another one with different load to readily adjust a touch load.
Preferably, in the aforementioned key for a musical instrument, the weight comprises a plurality of weights different in load from one another.
According to this preferred embodiment of the key, since there are a plurality of weights different in load from one another provided to select therefrom an appropriate one having a load to realize a desired touch feeling, the touch load can be more readily adjusted.